Creatorum Genius Lab Imago

Designed for creating rhythmic pads and basses, this 3-oscillator synth sports two filters, amp and filter envelopes, delay, EQ and a flanger. There's also a 32-step sequencer and, if you're feeling lucky, you can randomise all parameters with a single button press.

Mildon Studios HUE-X + M4GIQ Plugin Bundle

Two freebies in one bundle. HUE-X is an EQ that's designed for people who like to experiment with sound, giving you ten descriptively named faders to tweak. M4GIQ, meanwhile, is a multi-effect that enables you to apply gain, panning and delay to each frequency band, so you can spread frequencies across the stereo image.

Tonebytes Harmonaut

This ad-supported instrument is based on additive synthesis technology and comes with four waveform types and 32 harmonics that can be drawn with your mouse. You can also adjust the attack, decay, sustain and release for each harmonic, while a low-pass/high-pass filter, an LFO and chorus can be called into play, too.

TA Programming SubSonic

Billed as "the synth that takes you back," SubSonic is a subtractive instrument that promises to give you a vintage sound. Among its tools are three oscillators, a graphical ADSR envelope, a multimode filter and reverb, delay, chorus, flanger and warper modules.